Factors influencing COVID-19 vaccine uptake among adults in Nigeria

Background Emerging variants of Coronavirus disease 2019 (COVID-19) has claimed over 3000 lives in Nigeria and vaccination remains a means of reducing the death toll. Despite ongoing efforts by the government to ensure COVID-19 vaccination of most residents to attain herd immunity, myths and beliefs have adversely shaped the perception of most Nigerians, challenging the uptake of COVID-19 vaccine. This study aimed to assess the factors influencing the awareness, perception, and willingness to receive COVID-19 vaccine among Nigerian adults. Methods A cross-sectional online nationwide study was conducted from April to June 2021 among Nigerian adult population using the snowballing method. Descriptive analysis was used to summarise the data. Univariate and multivariate analysis was used to identify the predictors of COVID-19 uptake among the respondents. A p value <0.05 was considered significant. Results A total of 1058 completed forms were analysed and 63.9% were females. The mean age was 40.8 years±12.2 years. Most of the respondents (740; 69.5%) had satisfactory awareness of the vaccination exercise. The media was the main source of information. Health workers reported higher level of awareness (aOR = 1.822, 95% CI: 1.388–2.524, p<0.001). Respondents that are Christians and Muslims had better awareness compared to the unaffiliated (aOR = 6.398, 95% CI: 1.918–21.338, P = 0.003) and (aOR = 7.595, 95% CI: 2.280–25.301, p<0.001) respectively. There is average score for perception statements (566; 53.2%) towards COVID-19 vaccination. Close to half of the respondents (44.2%) found the short period of COVID-19 production worrisome. Majority of the respondents were willing to get the vaccine (856; 80.9%). Those without a prior diagnosis of COVID-19 had a lower willingness to get vaccinated (aOR = 0.210 (95% CI: 0.082–0.536) P = 0.001). Conclusion The study revealed a high level of awareness, willingness to receive the vaccine and moderate perception towards the vaccination activities. Influencing factors that significantly affects awareness were religion, occupation, education and prior diagnosis of COVID-19; for perception and willingness—occupation, and prior diagnosis of the COVID-19 were influencing factors.


Study design
A cross-sectional study was conducted from April to June 2021. A structured self-administered questionnaire was designed and incorporated into the Google survey tool (Google Forms). This was shared with the public on social media such as Facebook, WhatsApp, Telegram, Twitter, and LinkedIn using the generated link.

Study participants, sampling size and sampling
The study targeted eligible Nigerian residents. A sample size of 664 participants was computed for a population of 212million Nigerians [17] at a 99% confidence level, 5% margin of error and 50% response rate using the Open Source Epidemiologic Statistics for Public Health (OpenEpi), version 3 [18]. Participants were recruited using the Snowball sampling technique. The researchers posted the questionnaire on the various social media groups and in turn, these prospective respondents were encouraged to send to their own contacts and online platforms. Respondents were recruited irrespective of gender, cultural background, or origin, aged 18years and above while respondents that completed the questionnaire outside Nigeria were excluded. Those that did not consent could not complete the electronic questionnaire as it was a requirement to attempt the questions.

Data collection and analysis
The data collection tool was adapted from similar studies [4,9,19] and frequently asked questions in the media about COVID-19 vaccination. The questionnaire prepared in the English language took an average of 5 minutes to be completed. Participants were assured of confidentiality. The e-survey collected data on the following: socio-demographic information such as gender, age, religion, highest education level attained, residence, history of a chronic condition, history of travel, monthly income, and occupation (categorised as health workers and non-health workers); Awareness of participants regarding the first phase of COVID-19 vaccination had 4 items with a Yes or No options, willingness to receive the vaccine had 1 item. Also, information on the perceptions of respondents to the COVID-19 vaccine had10 items on a 5-point Likert scale (Strongly agree, agree, not sure, disagree and strongly disagree). The questionnaire was assessed for content validity by clinical pharmacists. A pilot study was carried out among 10 randomly selected social media participants for clarity, acceptability, and readability. This led to changes and modifications of some items and options before the final survey was distributed to the study population.
The data were sorted, coded, and analysed using IBM SPSS statistics version 24.0 software and Microsoft Excel 365. To summarize the data, descriptive statistics such as frequency and percentage were used for the sociodemographic characteristics. A numeric scoring pattern was used to assess the awareness, willingness, and perception levels of respondents to the first phase of the vaccination exercise. The outcome variables (awareness, perception, and willingness) were further categorized as 'satisfactory' or 'unsatisfactory' based on their individual mean scores from a maximum obtainable score which serve as cut-off marks. Scores above the mean scores obtained for these outcome variables were classified as 'satisfactory responses' and vice versa [20]. Inferential statistics (logistic regression model) was used. The logistic regression model was used to identify factors that influence awareness, perception, and willingness to get the COVID-19 vaccine. Univariate associations were ascertained with each demographic variable and the outcome variable (Crude odds ratio; cOR). A multivariable logistic regression model was also created to estimate associations (adjusted odds ratios; aOR) and 95% confidence intervals (CIs) with significance set at p = 0.05 were used [21].

Ethical consideration
Ethics approval was granted by the Health Research and Ethics Committee of Lagos University Teaching Hospital, Nigeria (HREC, LUTH) with approval number: ADM/DSCT/HREC/APP/ 4234. Participants in the study were informed about the procedure and purpose of the study in the first section on the Google form. Confidentiality of information provided was assured. All participants consented willingly to be a part of the study during the data collection periods by clicking on the consent button. All the data was collected anonymously and analyzed using the coding system.

Awareness, perception, and willingness towards COVID-19 vaccine
The mean awareness score was 2.9±0.8 ( Table 2). Most of the respondents (740; 69.5%) had satisfactory awareness of the first phase vaccination exercise. The media was the main source of information (Fig 1). The perception of participants (566; 53.2%) towards COVID-19 vaccination was satisfactory with a mean perception score of 35.0 ±6.5 ( Table 2). Most respondents accepted that the COVID-19 vaccine is effective at preventing the disease (814; 76.9%, obtained as sum of strongly agree and agree). Some respondents consented that the short period of COVID-19 production is worrisome (468; 44.2%, obtained as sum of strongly agree and agree) while some are neutral to this statement (311; 29.4%). On the perception that vaccines produced for Europe and America are safer, respondents perceived (465; 44%, obtained as sum of strongly agree and agree) while some respondents were neutral to this statement (390; 36.9%). Most of the respondents were willing to get the COVID-19 vaccine (856; 80.9%).
On willingness to receive COVID-19 vaccine, agreement was higher for those who are health workers in this survey (aOR = 4.83 (95% CI: 3.28-7.11) P< 0.001) than non-health workers. Also, there was low willingness to receive the vaccine among those without prior COVID-19 diagnosis (aOR = 0.21 (95% CI: 0.08-0.54) P = 0.001) as compared to those that previously had the virus (Table 5).

Discussion
This study aimed to assess the sociodemographic factors influencing the awareness, perception, and willingness of Nigerian adults towards the uptake of COVID-19 vaccine.
Findings from this study showed a positive population-level impact on awareness of COVID-19 vaccination in Nigeria. This is similar to a study carried out in Bangladesh where the majority of respondents were aware of the vaccination activities [5]. Contrary to this, a study carried out in Ethiopia at the commencement of the COVID-19 vaccination roll-out, however showed a low awareness of respondents [22]. The satisfactory score obtained by

PLOS ONE
Factors influencing COVID-19 vaccine uptake among adults in Nigeria respondents of this study showed the majority are aware of the COVID-19 vaccination exercise. This may be due to efforts made by the government. Before the commencement of the vaccination exercise in Nigeria, the government, in collaboration with UNICEF and other agencies such as the National Primary Health Care Development Agency (NPHCDA), embarked on raising awareness to address some of the bottlenecks to COVID-19 vaccine uptake. Sensitisation programs and Stakeholder's engagements with health workers, traditional and community leaders, community youth leaders, market women and those that can influence family and friends were held across the country. There were series of trainings as well as mobilisation and community enlightenment on the safety and importance of getting the COVID-19 vaccine [23]. In this study, being a Muslim or a Christian influences awareness of COVID-19 vaccination more than being unaffiliated. The low awareness of the unaffiliated may also be due to the small size of our sample. Gender and age did not significantly affect the level of awareness in this study, which was similar to a previous study [22]. This may be due to worldwide COVID-19 vaccine advocacy and the indiscriminate intensified efforts of the Nigerian government to ensure all residents, regardless of their demographic status, know about the arrival and commencement of the vaccination exercise. Enhancing situational awareness of information generates knowledge and behaviour that enables people to develop a mental model towards perception, comprehension and prediction of the future status of an event [24]. In this study, findings showed the main sources of COVID-19 vaccination information were the Media (television, radio, and newspapers), health workers and social media platforms. A similar study carried out in Poland showed experts' materials as a major source of information on COVID-19 vaccines [25]. Health workers and mass media have been identified as important sources of health information for the general population [26,27]. Doctors and other health workers have been identified as potential communicators through which messages emphasizing the medical and social benefits of the COVID-19 vaccine can be effectively disseminated [28]. To counter misinformation and improve trust, the NPHCDA in partnership with multinational media platforms in Nigeria, has engaged in various initiatives to ensure residents of Nigeria get credible information on COVID-19 vaccination. For instance, there was a range of Facebook frames and Instagram stickers that allowed people to share their support for getting vaccinated with their family and friends. The frames and stickers include banners with a statement such as 'Let's Get Vaccinated' or 'I Got My COVID-19 Vaccine' [29].
Findings from this study also showed varied responses to perception statements, although there was an overall moderately satisfactory response score. Most of the respondents showed a positive perception towards the effectiveness of the vaccine in preventing COVID-19 disease, but there were trust issues as to whether scientists had discovered a safe and effective COVID-19 vaccine or if the Nigerian government had ensured the safety of the vaccine. Almost half of the participants showed fear of the side effects of the vaccine. A survey carried out in France and French-speaking parts of Belgium and Canada showed distrust in the Ministry of Health to ensure the safety of the COVID-19 vaccine [19]. A global cross-sectional study carried out also revealed that half of the participants had safety concerns, especially related to the side effects of the COVID-19 vaccine. In Poland, a study carried out showed varied trust between the vaccines approved in Europe [25]. In a study carried out on trust in the COVID-19 vaccine in the United States, social and societal level factors such as vaccine fast-tracking, government distrust, uncertainty about the content of the vaccine and fear of side effects were highlighted as reasons for distrust of the COVID-19 vaccine [30].
On the influence of sociodemographic characteristics of respondents on perception statements in this study, Nigerian residents between the age range of 40-69 years were more likely to have a positive perception towards COVID-19 vaccine than those below this age range and those above 70 years. This may mean that people within the younger age group think they have better immunity and may not be necessarily vaccinated [31]. The elderly might have a perceived fear of the side effects and likely complications [32,33]. It may also be because the younger participants are more exposed to vaccine-related misinformation [31]. This may require further investigation. It is worthy of note that trust, confidence, and belief in a program influence the acceptance and successful outcome. The government should intensify efforts for the highest possible outreach through the major sources of information identified in this study. Safety issues with COVID-19 vaccines should be continuously addressed by tailoring clear and reliable targeted messages to promote engagement and acceptance.
The proportion of willingness to get vaccinated in this study was high among the participants and most of them were health workers. Participants with higher education (diploma and above) had higher odds of willingness to get vaccinated compared to participants with secondary school and lower education. This disparity in the willingness to get the COVID-19 vaccination was also found in a study carried out in the United States [34]. Therefore, increasing advocacy and awareness about the COVID-19 vaccine, especially among those with lower educational levels is paramount.
The common predictive factor that influences the awareness, perception, and willingness to get vaccinated in this study were occupation and prior diagnosis for COVID-19. Significantly, respondents who were health workers and those who were previously positive of COVID-19 disease had high awareness, positive perceptions and were more willing to get the vaccine. The influence of prior COVID-19 exposure of respondents to these outcome variables may be heightened due to their real-time experience of COVID-19 disease. Publicized experience sharing by people with a prior diagnosis of COVID-19 disease can give a sound picture of how deadly the disease can be and the essence of getting the vaccine.
Health workers were more likely to be willing to get vaccinated compared to non-health workers. As found in literature, the majority of those unwilling to receive the vaccine were non-health workers [35,36]. This might imply that the subsequent phases of the COVID-19 vaccination exercise, which involves the public, might experience a low turnout of people. Continuous targeted messages and education focusing on the effectiveness and safety assurance of the vaccine are essential to improve the COVID-19 vaccination exercise and increase uptake. There should be the active involvement of all cadres of health workers (physicians, pharmacists, nurses, community health workers, and others) in ensuring health education of COVID-19 vaccination programs. Healthcare workers play an important role in a successful vaccination program. Their knowledge and awareness determine a recommendation to nonhealth workers [26].

Study limitation
Nigerian residents that could not communicate in the English language could not partake in this study. Nigerian residents who do not have android phones could not partake in the study. The convenient sampling method also made respondents skewed towards Southwest of Nigeria than other parts. The electronic sampling method used might have introduced selection bias as those without access to the internet were not involved in this study. These may affect fair representation and findings. However, this is the safest method that could be adopted during this pandemic to reduce the exposure of researchers.

Conclusion
The current results provide information on the public responses to the COVID-19 vaccination in Nigeria. The study revealed a high level of awareness, willingness to receive the vaccine and moderate perception towards the first phase of vaccination activities. The current study suggests factors such as education, religion, occupation, and prior diagnosis of COVID-19 disease as predictive variables that influence awareness of vaccination exercise. It also indicated occupation and prior diagnosis of the COVID-19 disease as predictive factors that influence the perception and willingness for the vaccine uptake. Health workers were more willing to receive the vaccine than non-health workers. Data from this study identified vaccine distrust and safety concerns as part of perception issues that must be addressed in Nigeria for increased uptake of the COVID-19 vaccine. It is the responsibility of policymakers to ensure continuous COVID-19 vaccine targeted messages are passed through the major channel of information identified in this study (media and health workers).
Findings from this study will enable stakeholders and strategic planners to intensify efforts on related awareness and health education programs that will improve perception and willingness, especially of non-health workers, to ensure a successful vaccination process in subsequent phases.